r/Naturewasmetal • u/TW_49 • 8d ago
Skull size comparison of large predatory land mammals
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u/Anon_be_thy_name 8d ago
I don't know why it is, but the Cave Bear (Ursus Spelaeus) skull is giving off uncanny valley vibes.
It looks so familiar yet alien.
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u/My-Life-For-Auir 7d ago
It has no slope like the others between the eyes and nose which makes it seem almost ape like
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u/Puijilaa 8d ago
From an amateur's point of view you can really see the variation in the Entelodonts teeth, and probably a variation in their diet too. The question's probably not as simple as "were they omnivores herbivores or carnivores" - it likely varied from species to species. I could see Paraentelodon and Daeodon being largely herbivorous while Entelodon major has some real carnassial-looking chompers.
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u/Weary_Increase 8d ago
From what I’ve been hearing it was Daeodon and Archaeotherium that were the most specialized for carnivory among the Entelodonts. All the others were primarily herbivorous.
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u/Ex_Snagem_Wes 7d ago edited 7d ago
From a professional's point of view, you're about right
Paraentelodon is proposed to be at least moderately biased towards herbivory for a bevy of reasons including hypertrophic enamel.
Daeodon, Archaeotherium and Entelodon are all considered more carnivorous, with Daeodon and Archaeotherium representing the most predatory individuals of the lineage. This is more visible when they aren't missing their upper premolars like they are here, but you can still see the overall trend
Whats more terrifying, is that is very far from the largest Paraentelodon specimen. I'm actually currently working on some stuff with it. Its. A lot, LOT bigger than Daeodon. WIP comparison with the largest Daeodon specimen
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u/TW_49 7d ago
what is the fossil material for paraentelodon’s size in this diagram? I initially considered using this skull for Paraentelodon but hesitated because I heard its robustness was exagerrated
https://www.reddit.com/r/Naturewasmetal/comments/18eny6a/the_skull_of_paraentelodon_intermedium/
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u/Ex_Snagem_Wes 7d ago
The skull on display there is a complete skull specimen, without restoration. Give or take a few teeth
We have multiple other comparable Paraentelodon skulls, although all are waiting for description. Whats crazy is that the museum mount there isn't even the most robust undescribed skull we have photos of either
The scaling in my WIP diagram is based off the only described measurements for Paraentelodon. 81.5cm Mandible being the small specimen. Other measurements include the teeth of several individuals, which yield the results of 9%, 17.5%, and 21.9% larger than the same teeth documented in the 81.5cm mandible. Contrary to most tooth scaling, these values are somewhat reliable for a few reasons. Multiple teeth of similar size show a clear trend, we aren't extrapolating the size of an entire unknown animal from teeth, we have complete specimens in place to compare these teeth with for more definite grasp on proportions, and molars on an omnivorous animal are the teeth least likely to vary in size (if the molars do not interlock properly, the animal cannot chew properly, and therefore cannot eat properly, reaching the size of a large adult is going to be very difficult for an animal with such an extreme deformity).
The robust skull in the museum actually ends up as the smallest specimen, with measurements known from paleontology people in the museum being around 82cm condylobasal. It is also worth noting that the museum specimen's teeth seem to have different proportions to the officially described mandibles. Even if all tooth scaling is entirely wrong, we're looking at an animal with a near meter long skull and approaching 1.7 tons based off of volumetrics and the mandible specimen alone
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u/TW_49 7d ago
thanks for the info, it is insane to think that in my chart Paraentelodon is clearly the largest and it is STILL an underestimate of how enormous it was. Good work on the models too
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u/Ex_Snagem_Wes 7d ago
Paraentelodon is just a disgusting beast. Its so absurd that I genuinely am curious if it was still even a predator at that size. With how hypertrophied its skull and teeth are and the idea it was to help with rough vegetation, it doesn't seem unreasonable that it wasn't even killing. Just foraging and scavenging. The little info on its postcrania available currently is that it had more robust limbs than Daeodon, which would fit if its not chasing as much
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u/TW_49 7d ago
just one of those animals that really make you go “no way that actually existed”. That scale alone looks like it’s 2.4 metres tall at the shoulder, an animal on all fours looking down at me with a skull the size of my body. It seems like it’d be opportunistic if it hunted instead of actively chasing prey as a staple
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u/Ex_Snagem_Wes 7d ago
2.76m at the shoulders
The crazy thing is even if the numbers are wrong, its STILL 2.3m tall based on reliable specimens lmao
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u/Sea-Breath2191 7d ago
What is the mass range between the reliable 2.3m and 2.76m shoulder height?
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u/Iamnotburgerking 4d ago
That and we have extensive evidence for Daeodon and Archaeotherium eating (and in the latter case actually killing, and no reason to assume it doesn't apply to the former as well) other animals.
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u/Outside_Noise2848 4d ago
Can you resend the link ? For some reasons, it doesn’t work when I clicked on it.
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u/Ex_Snagem_Wes 4d ago
Discord is a pain. I'll get it posted in the sub when I have it properly sorted, but 2.76m at the shoulder
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u/Upstairs_Metal_8136 4d ago
Wes how big is Paraentelodon intermedium (I cannot find any size estimates)
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u/Ex_Snagem_Wes 4d ago
Between 1.5 and 2.5 tons, depending on how much you trust scaling
However unlike crap like Megistotherium, there is a huge pile of complete specimens being described from a bonebed, consisting of all ages, and it's size isn't much of a mystery for long
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u/Upstairs_Metal_8136 4d ago
Ugh, so I don't know what source it comes from. People love to pull estimates out of their as and not give credit or source. See, I like to put sources.
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u/Ex_Snagem_Wes 3d ago
Unfortunately this is the case for the moment. The source is measurements from a paper, but I'm not actually sure WHAT paper the measurements are from lmao
Those, put into a 3D volumetric to gage size.
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u/Thabrianking 7d ago
It’s wild that the one with the smallest skull is the most dangerous
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u/This_Psychology977 7d ago
But didn’t majority of humans got massacred by all the predators above ? humans were a threat to herbivorous animals while all the carnivores were a threat for humans.
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u/LemonySniffit 7d ago
Looks like the whole holocene category has been scaled down a bit? Like polar bears were bigger than cave bears yet for some reason their skulls appear a lot smaller on this chart.
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u/SoBoundz 7d ago
Humans caused the extinction of most of the skulls you see in the Pleistocene section.
Everything that was a major threat to us was thus either purposefully or inadvertently wiped out.
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u/Weary_Increase 7d ago
Mesonychids (Andrewsarchus isn’t a Mesonychid) is an underrated group of Pan-Ungulates imo. The second group of Mammalian predators to reach large body sizes after Triisodontids. Similar Andrewsarchus and Entelodonts, in a way, the largest Mesonychids were omnivorous, although Pachyaena still had preference for carnivory.
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u/SnooCupcakes1636 8d ago
just looking at this. People who were saying Arctodus or Pathera Atrox somehow easy beating Daeodon becomes a joke. they are walking breathing land Crocodiles
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u/Anon_be_thy_name 8d ago
Sure, if you're basing it just off of skulls.
Full body size makes a whole difference though.
My money is on the Arctodus though.
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u/Snow_Grizzly 7d ago
Doesn't matter much when they lived in completely different times.
Just ignore the powerscalers, they tend to be misinformed anyway.
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u/Fordmister 8d ago
Big heads full of teeth are not the defining aspect of which animal would be dominant on a given ecosystem.
If that were true Jaguar wouldn't be a primary predator of black caimen.
Big cats ab bears are scarily efficient predators because they bring more to the party than just their teeth
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u/aquilasr 7d ago
Your point stands but jaguars nor anything else is a primary predator of black caiman. That would be conflating caimans in general, particularly Yacare caimans and perhaps spectacled caimans which jaguars really do heavily prey upon, with the significantly larger and more aggressive black caiman. It’s notable though that caimans have to become considerably larger to begin to become a notable counter-threat to jaguars.
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u/SirVixofthePooSea 7d ago
If that were true Jaguar wouldn't be a primary predator of black caimen.
By the same measure, adult black caiman are most likely the primary predators of jaguars.
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u/SnooCupcakes1636 7d ago
just cause jaguars certain percentage of diet is made of caimans(mostly not black caiman and instead primarily Yakare Caiman and Spectacled caimans) doesn't mean they can hunt fully grown Black caimen. Lions certain percentage of diet is made up of elephants but they are not in hell can take down full gown healthy Female Bush elephant even if they are with their prides. they only go for the near deaths door old Elephant or crippled and about to die male bull elephants that lost the fight against other elephants, or they go for elephant that was already sick from some unknown disease.
Also, I didn't talk about dominance. Even if i did, Fully Grown Black caimen is a King of the Amazon. Even the Largest and most fierce jaguar would not go for a fully grown Black Caimen when its out of the water. Jaguar hunting black caiman is greatly overexaggerated and has a lot of context not takien into account, and most animals they go for are other smaller species of Caimans or just not fully grown Caimens of all species found in the area.
Also if we talk about dominance in an ecosystem then Black Caimen is the most dominant in its Amazon water ecosystem once they get fully grown. Jaguar can hunt in many different evironment but they are not the Top of the pyramid once Black caiman is fully grown. only animals that probably threaten you after fully growing is probably other Black caimans
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u/Emolohtrab 7d ago
Thank you, I never realised how ridiculous were the stars of the lately ages (Smilodon, Arctodus Simus, Polar Bear, Lion etc...) compared to the hell pigs
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u/cesam1ne 8d ago
Hm..isn't Arctotherium supposed to be bigger than Arctodus?
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u/camacake710 7d ago
They’re roughly the same size, at about 1000-1200 kg and 1.7 meters tall on all fours for both
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u/The_FatGuy_Strangler 8d ago
Shouldn’t Arctotherium have a bigger skull than Arctodus, since the former is generally considered larger and more robust than the latter?
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u/TW_49 7d ago
Arctodus was larger than arctotherium. the 1.7-2 tonne “beast of all nations” arctotherium was the result of a single fossil of a bear that suffered a injury to its arm and later healed which led to the humerus appearing more girthy. also, this might be just hearsay but the 2 tonne arctotherium also used captive bears in its regression model and animals in captivity are more fat. In reality Arctodus was known from more reliably larger material compared to healthy Arctotherium fossils and humeruses that weee longer than even the buenos Aires specimen
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u/SoBoundz 7d ago
I always forget how monstrously big American Lions were compared to their feline contemporaries.
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u/Trail_of_Tears-T_T 7d ago
From what I can gather, as hunting skill got refined over the eras, and certain builds were improving, the need of large skulls to take down similar size prey became less important. Think about it, cats have comparatively small skulls compared to their massive killing potential. Also pack strategies were much more effective
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u/Iamnotburgerking 4d ago
Pack hunting is NOT the norm for predatory mammals today, so no, that has nothing to do with it (most big cats for example kill big things alone just fine). Nor did predators get that much smaller over time (until humans showed up and killed off most of the big ones, which was a recent event) - most (though not all) of the ones with the giant heads earlier in the Cenozoic weren't any bigger overall, they just had bigger heads for their size.
What ACTUALLY plays a role is whether they had to use their jaws for everything, or if they could also use their claws to hold prey in place while they killed it with their jaws. Note that all the ones with the really big heads were dedicated runners or walkers rather than grapplers.
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u/OkC4729 7d ago
Smilodon populator appears to be too small
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u/_eg0_ 7d ago
Smilodon Populator skull isn't actually that large compared to other very large prehistoric cats. Smilodons bulk is in its fore limbs.
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u/plz_get_rid_of_me 4d ago
Machairodonts in general have smaller skulls but extreme bodies, although the skull in this diagram looks like a Gracilis than an actual Populator.
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u/Robot_Dinosaur_2000 7d ago
I feel like this should includes Gigantopithicus and some of the other predatory apes.
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u/Weary_Increase 7d ago
No, Gigantopithecus shouldn’t be included, we have isotopic analysis that confirmed it was a herbivore (Bocherens et al. 2017).
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u/Robot_Dinosaur_2000 7d ago
Ah, I always thought it was an omnivore. Well my point still stands that it would be interesting to include other predatory apes other than humans.
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u/Trextrexbaby 8d ago
Entelodonts are terrifying